Vapor-condensing device



United States Patent Morris N. Crandall 8177 Stratford, St. Louis, Missouri 63105 756,069

Aug. 28, 1968 Aug. 18, 1970 Inventor Appl. No. Filed Patented VAPOR-CONDENSING DEVICE 7 Claims, 5 Drawing Figs.

US. Cl 123/119, 55/44.4, 62/285, l23/4l.2, 165/110 Int. Cl F02f 9/00 Field of Search 165/ 1 10- [5 6] References Cited UNlTED STATES PATENTS 2,756,028 7/1956 Byerley l65/l 13(1 13)UX 3,250,263 5/1966 Gerjets 123/119 Primary Examiner- Wendell E. Burns Attorney-Kingsland, Rogers, Ezell, Eilers and Robbins ABSTRACT: A vapor-condensing device, interposed between the crankcase and an intake of an internal combustion engine, has baffles therein which cause vapors from the crankcase to flow along a cooling surface and then expand; and the resulting condensate is collected in a removable receptacle.

VAPOR-CONDENSING DEVICE This invention relates to improvements in vapor-condensing devices. More particularly, this invention relates to improvements in a device which can condense undesirable hydrocarbon vapors from the gases and vapors which issue from the crankcase of an internal combustion engine.

It is, therefore, an object of the present invention to provide a device which can condense undesirable hydrocarbon vapors from gases and'vapors which issue from the crankcase of an internal combustion engine.

In the operation of internal combustion engines, small quantities of the products of combustion referred to as blowby" slip past the piston rings and enter the crankcases of those engines. The gases and vapors within the crankcases of those engines tend to entrain the hydrocarbon vapors from the blow-by and from the lubricating oil within those crankcases. For many years, the gases and vapors and their entrained hydrocarbon vapors were permitted to vent freely through the breather pipes and oil-filling caps of internal combustion engines; but progressively greater efforts have recently been made, and are now being made, to prohibit the escape of such gases and vapors and entrained hydrocarbon vapors from the crankcases of internal combustion engines.

In their efforts to keep gases and vapors and entrained hydrocarbon vapors from escaping from the crankcases of internal combustion engines, some manufacturers of internal combustion engines have provided connections between the crankcases and the intake manifolds of their engines. Those connections include check valves; and those connections enable the reduced pressures in the intake manifolds of those engines to maintain reduced pressures within the crankcases of those engines. Because the pressures in the crankcases of those internal combustion engines are subatmospheric, there is no tendency for gases and vapors and entrained hydrocarbon vapors to escape from those crankcases; and, instead, the gases and vapors and entrained hydrocarbon vapors mix with the fuel in the intake manifolds of thoseengines and pass into the cylinders of those engines.

While the connections between the crankcases and intake manifolds of internal combustion engines are helpful and useful in preventing the escape of the gases and vapors and their entrained hydrocarbon vapors, those connections are hurtful because some of the hydrocarbon vapors entrained by the gases and vapors form objectionable deposits on the intake valves of the engines. Also, some of those hydrocarbon vapors form objectionable deposits in the check valves of those connections. As a result, after an engine has been operated for a time, the intake valves of that engine can tend to stick in their open positions, and the check valve in the connection between the crankcase and the intake manifold can tend to stick in its closed position. Both of these results are objectionable. It would be desirable to provide a device that would substantially condense undesirable hydrocarbon vapors, which enter the connection between the crankcase and intake manifold of an internal combustion engine, before those hydrocarbon vapors could reach the valve in that connection; because such a device could keep those hydrocarbon vapors from interfering with proper operation of that valve and of the intake valves. The present invention provides such a device; and it is, therefore, an object of the present invention to provide a vapor-removing device in the connection between the crankcase and intake manifold of an internal combustion engine which can substantially condense undesirable hydrocarbon vapors, which enter that connection, before those hydrocarbon vapors can reach the valve in that connection.

The vapor-condensing device provided by the present invention is mounted in the stream of cooling air which flows over the internal combustion engine with which it is used; and hence that vapor-condensing device is cooler than the hydrocarbon vapors which issue from the crankcase of that engine. In addition, that vapor-condensing device has baffles therein which force the hydrocarbon vapors to initially flow through a passage of narrow cross section which has one wall thereof cooled by the stream of cooling air that flows over the engine, and then permit the cooled hydrocarbon vapors to expand in a second passage of larger cross section. As the hydrocarbon vapors pass through the first passage, some of the heat therein is extracted from them; and then, as those cooled vapors move into the second passage, they expand and experience sufficient additional cooling to condense. The resulting condensate drains toward the bottom of the vaporcondensing device and enters a removable receptacle. That receptacle can be emptied periodically; and hence the vaporcondensing device of the present invention can keep some of the hydrocarbon vapors, which issue from the crankcase, from entering the intake of the engine; as by collecting those hydrocarbon vapors in a removable receptacle in the form of condensate. It is, therefore, an object of the present invention to provide a vapor-condensing device which can be interposed between the crankcase and an intake of an internal combustion engine, and which has baffles that provide a passage of small cross section with a cooled wall as one side thereof and that provide a second passage of larger cross section in which the hydrocarbon vapors can condense.

The vapor-condensing device provided by the present invention forces undesirable hydrocarbon vapors, that are introduced into it, to recurrently change direction and to follow a serpentine path. As those undesirable hydrocarbon vapors recurrently change direction and follow that serpentine path, they are progressively cooled; and are thus given a full opportunity to condense and drain into the removable receptacle. Consequently, large quantities of undesirable hydrocarbon vapors, that are introduced into the vapor-condensing device provided by the present invention, are converted to condensate and are collected in the removable receptacle. It is, therefore, an object of the present invention to provide a vaporcondensing device which has baffles therein that positively force undesirable hydrocarbon vapors introduced into that vapor-condensing device to recurrently change direction and to follow a serpentine path.

Other and further objects and advantages of the present invention should become apparent from an examination of the drawing and accompanying description.

In the drawing and accompanying description a preferrred embodiment of the present invention is shown and described but it is to be understood that the drawing and accompanying description are for the purpose of illustration only and do not limit the invention and that the invention will be defined by the appended claims.

In the drawing, FIG. 1 is a schematic representation of an internal combustion engine on which a preferred embodiment of vapor-condensing device provided by the present invention is mounted,

FIG. 2 is a partially-sectioned view, on a larger scale, through the vapor-condensing device shown in FIG. 1, and it is taken along the plane indicated by the line 2-2 in FIG. 1,

FIG. 3 is a sectional view, on the scale of FIG. 2, through the vapor-condensing device shown in FIG. 1, and it is taken along the plane indicated by the line 3-3 in FIG. 2,

FIG. 4 is a further sectional view, on the scale of FIG. 2, through the vapor-condensing device shown in FIG. l, and it is taken along the plane indicated by the line 4-4 in FIG. 3, and

FIG. 5 is a partially broken-away, partially-sectioned view, on the scale of FIG. 2 through the vapor-condensing device shown in FIG. 1, and it is taken along the plane indicated by the line 5-5 in FIG. 2.

Referring to the drawing in detail, the numeral 20 generally denotes an internal combustion engine of standard form which has a carburetor 22, an air cleaner 24, and an intake manifold 26. A vapor-condensing device 28, provided by the present invention, has the inlet 44 thereof connected to the crankcase of the engine 20 by a tube 30. The outlet 48 of that vapor-condensing device is connected to the inlet port of a check valve 32 by a tube 34. The outlet of the check valve 32 is connected to the intake manifold 26 by a tube 36. The vapor-condensing device 28 has a drain connection 40 to which a condensate receptacle 38 is releasably secured by screw threads. In one preferred embodiment of the present invention the condensate receptacle 38 is a transparent, glass jar so the amount of condensate which collects within it can be readily ascertained.

The vapor-condensing device 28 has a wall 42 which has a generally-rectangular upper portion and a frusto-triangular lower portion; and the inlet 44 is located in the upper portion of that wall. A second wall 46 of the vapor-condensing device 28 is similar to the wall 42; and the outlet 48 is located in the upper portion of that wall. The walls 42 and 46 have the tops, sides and bottoms thereof closed by a top wall 43, a bottom wall 45, and side walls 50 and 52; and the drain connection 40 extends through that bottom wall. The seams between the walls 42 and 46 and top wall 43, bottom wall 45. and side walls 50 and 53 are airtight. The lower portions ofthe side walls 50 and 52 incline downwardly and toward each other to conform to the frusto-triangular lower portions of the walls 42 and 46.

The numeral 54 denotes a baffle which is L-shaped in crosssection, and which is generally similar to the wall 42 in elevation. That baffle is spaced a short distance inwardly from the wall 42; and the foot of that baffle overlies but is spaced a short distance above the drain connection 40. The upper part of the baffle 54 is in register with the inlet 44; and it positively prevents a straight-line path for gases and hydrocarbon vapors between the inlet 44 and the outlet 48. The foot of the baffle 54 extends to the wall 46, as shown by FIG. 2 and 4. The lower portions of the sides of the baffle 54 are cut away to define elongated openings 56 and 58 between the lower portions of those sides and the lower portions of the side walls 50 and 52.

The numeral 60 denotes a baffle which has a generally rectangular upper end and a frustotriangular lower end; and that baffle is spaced inwardly of the baffle 54. The lower edge of baffle 60 abuts the foot of the L-shaped baffle 54; and that lower edge coacts with that foot to force essentially all of the gases and hydrocarbon vapors to move upwardly between the baffles 54 and 60. However, the baffle 60 has a small drain hole 62 therein adjacent the bottom edge thereof to permit condensate to flow through that baffle. While the drain hole 62 is large enough to permit condensate to flow through it, that drain hole is too small to let any appreciable quantities of gases and hydrocarbon vapors flow through it. The upper end of the baffle 60 is disposed an appreciable distance below the top wall 43 of the vapor-condensing device 28 to permit gases and hydrocarbon vapors to pass above that upper end.

A third baffle 64 is disposed intermediate the baffle 60 and the wall 46; and that third baffle has a generally-rectangular upper end and a frusto-triangular lower end. The upper end of the baffle 64 abuts the top wall 43 of the vapor-condensing device 28, and thus is squarely in register with the outlet 48. As a result, that baffle obviates a straight-line path, for gases and hydrocarbon vapors, between the space above the top of baffle 60 and the outlet 48. The lower end of the baffle 64 is spaced an appreciable distance above the foot of the baffle 54, and thus permits gases and hydrocarbon vapors to pass freely between that lower end and that foot.

Fins 66 are provided at the exterior of the vapor-condensing device 28, and to those fins will preferably be bonded to the walls 42 and 46 and to the side walls 50 and 52. Where that is done, those fins will be able to absorb substantial quantities of heat from those walls and side walls; and those fins will transfer those quantities of heat to the cooling air flowing over the internal combustion engine 20. Because the temperature of the gases and hydrocarbon vapors which enter the inlet 44 is about two hundred degrees Fahrenheit, and because the temperature of the cooling air flowing over the internal combustion engine is always below that temperature, the fins 66 are able to keep the vapor-condensing device 28 cooler than those gases and hydrocarbon vapors.

The baffle 54 is closer to the wall 42 of the vapor-condensing device 28 than the baffle 60 is to the baffle 54, as shown by FIGS. 2 and 4. As a result the passage 68, defined by the wall 42 and the baffle 54, has a cross section which is smaller than the cross section of the passage 70, defined by the baffle 54 and the baffle 60. The passage 72, defined by the baffles 60 and 64, and the passage 74, defined by the baffle 64 and the wall 46 of the vapor-condensing device 28, have cross sections which are similar to the cross section of the passage 70. In one preferred embodiment of the present invention, the walls 42 and 46 are three and one-half inches tall, the upper ends of those walls are three inches long, and those walls are spaced one inch apart. The baffle 54 is spaced from the wall 42 about one-sixteenth of an inch, and the baffle 60 is spaced from the baffle 54 approximately one-quarter of an inch; and hence the cross section of the passage is about four times as large as the cross section of the passage 68. The passages 68, 70, 72 and 74 coact to provide a serpentine path, between the inlet 44 and the outlet 48, for gases and hydrocarbons entering that inlet.

In the operation of the internal combustion engine 20, a reduced pressure will be established and'maintained within the intake manifold 26. The check valve 32 will respond to that reduced pressure to open; and, thereupon, gases and hydrocarbon vapors will be drawn upwardly from the crankcase of the engine 20, and those gases and hydrocarbon vapors will pass through the tube 30 and into the inlet 44 of the vapor-removing device 28. Those gases and hydrocarbon vapors will be forced to change direction by the baffle 54, and those gases and hydrocarbon vapors will be forced to move downwardly through the narrow cross-section passage 68 defined by that baffle and the wall 42. Because the stream of cooling air flowing over the engine 20 directly cools the wall 42 and also cools the fins 66 attached to that wall, the gases and hydrocarbon vapors flowing through the passage 68 will have substantial quantities of heat withdrawn from them. Those gases and hydrocarbon vapors will not pass under the foot of the L-shaped baffle 54; and, instead, will move through the elongated openings 56 and 58 between the lower portions of the sides of the baffle 54 and the lower portions of the side walls 50 and 52. In keeping the gases and hydrocarbon vapors from flowing directly over the drain connection 40, the foot of the L-shaped baffle 54 keeps the movement of those gases and hydrocarbon vapors from interfering with the movement of condensate through that drain connection.

As the gases and hydrocarbon vapors enter the passage 70, defined by the baffles 54 and 60, those gases and hydrocarbon vapors will experience an increase in volume and a decrease in velocity. That increase in volume will provide a further decrease in the temperature of those gases and hydrocarbon vapors; and some of the hydrocarbon vapors will change from the vapor state to the liquid state and drain downwardly along the confronting surfaces of the baffles 54 and 60. Also as the gases and hydrocarbon vapors enter the passage 70, the baffle 60 will force those gases and hydrocarbon vapors to change direction and to move upwardly toward the top wall 43 of the vapor-condensing device 28. The edges ofthe baffle 60 will be cooled by the side walls 50 and 52 of that vapor-condensing device, and so will the upper portions of the L-shaped baffle 54; and hence the gases and hydrocarbon vapors will experience further cooling as they pass upwardly through the passage 70.

As the gases and un-condensed hydrocarbon vapors reach the upper end of the passage 70, the baffle 64 will force those gases and un-condensed hydrocarbon vapors to change direction and move downwardly through the passage 72. Thereafter those gases and un-condensed hydrocarbon vapors will pass beneath the baffle 64 and change direction and move upwardly through the passage 74 until they reach the outlet 48. The side edges of the baffle 64 will be cooled by the walls 50 and 52 and the top edge will be cooled by the top wall 43, and hence that baffle will provide additional cooling of the gases and un-condensed hydrocarbon vapors moving through the passages 72 and 74. The wall 46 will be cooled directly by the stream of cooling air flowing over the internal combustion engine 20 and also will be cooled by the fins 66 attached to it; and hence that wall will provide additional cooling of the gases and un-condensed hydrocarbon vapors moving upwardly through the passage 74. Any hydrocarbon vapors which are converted from the vapor state to the liquid state in the passages 72 and 74 will flow downwardly along the confronting surfaces of the baffles 60 and 64 or along the confronting surfaces of baffle 64 and wall 46 and collect atop the foot of the L-shaped baffle 54. The resulting condensate will then flow through the drain hole 62 in the baffle 60, through one or the other or both of the openings 56 and 58, and downwardly through the drain connection 40 into the condensate receptacle 38.

The gases and any un-condensed hydrocarbon vapors which reach the outlet 48 will pass through the tube 34, through the check valve 32, and through the tube 36 to the intake manifold 26, where they will be drawn into the cylinders of the internal combustion engine 20. The condensing of large quantities of condensable hydrocarbon vapors, and the collection of those hydrocarbon vapors in the form of condensate in the condensate receptacle 38, are very desirable; because those vapors could form deposits within the check valve 32 or on the intake valves of the internal combustion engine 20. Any and all such deposits would be objectionable, and they could lead to improper operation of that check valve and of those intake valves.

The amounts of condensable hydrocarbon vapors that develop within the crankcase of an internal combustion engine are relatively high. For example, in one eleven hundred mile test with a 1968 automobile that had only twenty-six hundred miles on it at the beginning of that test, a total of about three ounces of condensate was collected in the condensate receptacle 38. That condensate had appreciable amounts of lead or lead compounds in it; and that lead or those lead compounds would have tended to coat or to cling to the undersurfaces of the intake valves of the internal combustion engine if they had not been removed by the vapor-condensing device 28. Those undersurfaces attain temperatures of close to seven hundred degrees Fahrenheit; and, at those temperatures, any lead or lead compounds which engaged those undersurfaces would tend to coat or cling to those undersurfaces, By collecting that lead and those lead compounds plus the other condensates which form as the condensable hydrocarbon vapors condense, the vapor-condensing device 28 provided by the present invention keeps that condensate from forming deposits in the check valve 32 or on the intake valves of the internal combustion engine 20.

In the vapor-condensing device 28 provided by the present invention, the gases and hydrocarbon vapors which enter the inlet 44 are progressively cooled during their movement through the passages 68, 70, 72 and 74. Those gases and hydrocarbon vapors are recurrently forced to change direction as they follow the serpentine path formed by those passages; and, in addition, those gases and hydrocarbon vapors experience a material decrease in velocity and a corresponding material increase in volume as they enter the passage 70. The overall result of the progressive cooling of the condensable hydrocarcarbon vapors, of the recurrent changes in the direction of flow of those hydrocarbon vapors, and of the material expansion in volume and material decrease in velocity of those hydrocarbon vapors is the condensing of large quantities of condensable hydrocarbon vapors, which otherwise could form deposits in the check valve 32 and on the inlet valves of the internal combustion engine 20. This, despite the fact that there are no moving parts in the vaporcondensing device 28, and despite the fact that it absorbs little, if any, of the power developed by the internal combustion engine 20.

Whereas the drawing and accompanying description have shown and described a preferred embodiment of the present invention, it should be apparent to those skilled in the art that various changes may be made in the form of the invention without affecting the scope thereof.

lclaim:

l. A vapor-condensing device which can be connected between the crankcase and an intake of an internal combustion engine and which comprises:

a housing which has an inlet connectable to said crankcase of said internal combustion engine and which has an outlet connectable to said intake of said engine,

a plurality of baffles that are positioned within said housing and that coact with said housing and with each other to define a serpentine path,

one of said baffles coacting with one wall of said housing to define a passage within said housing, adjacent said one wall of said housing, that constitutes one pass of said serpentine path and that cools vapors passing through it,

another of said baffles coacting with said one of said baffles and with said housing to define a second passage in said housing, spaced from said one wall of said housing, that constitutes a second pass of said serpentine path and that cools vapors passing through it,

a connection between the inlet of said second passage and the outlet of the first said passage which causes vapor flow in said second passage to be angularly displaced from the vapor flow in the first said passage, and

a drain connection which permits vapors that condense in said passages to drain from said housing,

the first said passage and said second passage cooling vapors introduced into said inlet of said housing, and the cooling of said vapors plus the angular displacement of the vapor flows in the first said and said second passages causing said vapors to condense in said passages,

said baffles and said housing being fixed and unyielding and fixedly and unyieldingly defining said serpentine path to force substantially all uncondensable gases and vapors which enter said inlet to follow said serpentine path to reach said outlet.

2. A vapor-condensing device as claimed in Claim 1 wherein the cross section of said second passage is larger than the cross section of the first said passage, whereby vapors passing from the first said passage into said second passage experience a decrease in velocity and an increase in volume.

3. A vapor-condensing device as claimed in Claim 1 wherein said one baffle is elongated and is interposed between, and forms a wall of each of, the first said and said second passages, and wherein one end of said baffle is bent so it overlies, but is spaced above the level of, said drain connectron.

4. A vapor-condensing device which can be connected between the crankcase and an intake of an internal combustion engine and which comprises:

a housing which has an inlet connectable to said crankcase of said internal combustion engine and which has an outlet connectable to said intake of said engine,

a baffle which is disposed within said housing and which is located between said inlet and said outlet and which keeps vapors entering said inlet from flowing in a straight line between said inlet and said outlet, whereby said vapors must change direction after they enter said inlet,

a second baffle which is disposed within said housing and which is located between the first said baffle and said outlet and which keeps vapors passing the first said baffle from moving in a straight line to said outlet,

whereby said vapors must experience a second change of direction in passing from the first said baffle to said outlet,

the first said baffle helping define a passage at that face thereof which confronts said inlet, and helping define asecond passage at that face thereof which confronts said second baffle,

the first said and said second baffles coacting with said housing to cool vapors flowing through the first said and said second passages,

the first said and said second baffles forcing vapor flow in said second passage to be angularly displaced from the vapor flow in the first said passage,

the first said and said second baffles facilitating the condensing of vapors flowing through the first said and said second passages, and a drain connection which permits vapors that condense in said passages to drain from said housing, said baffies and said housing being fixed and unyielding and fixedly and unyieldingly defining a serpentine path to force substantially all uncondensable gases and vapors which enter said inlet to follow said serpentine path to reach said outlet. 5. A vapor-condensing device as claimed in Claim 4 wherein said second passage has a cross section materially larger than the cross section of the first said passage, whereby the vapors flowing through said housing experience a material increase in volume and a corresponding material decrease in velocity as they pass the first said baffle and move toward said second baffle.

6. A vapor-condensing device as claimed in Claim 4 wherein the first said baffle is L-shaped, and wherein said second baffle extends to and abuts the foot of the first said baffie.

7. A vapor-condensing device as claimed in Claim 4 wherein the first said baffle is L-shaped, and wherein the foot of the first said baffle overlies but is spaced above the level of said drain connection. 

